You could simply give the parent panel a title and make this collapsible, then add the tabpanel as you have done already.

But then are you wanting the tabs to actually be in the space where the title is displayed? This will be possible with some CSS (moving the panel body up and over the header), but then you will likely run into problems regarding panel height, and if numerous tabs are added, they will overlap or run under the collapse button in the title bar...